• Communications for Statistical Applications and Methods
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• v.27 no.2
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• pp.177-187
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• 2020

This article is concerned with the issue of forecasting and evaluation of threshold-asymmetric volatility models for time series of count data. In particular, threshold integer-valued models with conditional Poisson and conditional negative binomial distributions are highlighted. Based on the parametric bootstrap method, some evaluation measures are discussed in terms of one-step ahead forecasting. A parametric bootstrap procedure is explained from which directional measure, magnitude measure and expected cost of misclassification are discussed to evaluate competing models. The cholera data in Bangladesh from 1988 to 2016 is analyzed as a real application.

• Fashion & Textile Research Journal
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• v.12 no.5
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• pp.642-649
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• 2010

This study was designed to generate briefs pattern for women in their twenties using 3D parametric body model. 151 women in their 20's were random sampled and measured using Martine's anthropometry. And one subject was chosen as the representative subject for 3D scanning. Parametric model was generated of using CATIA P3, Unigraphics NX4.0, Rapidform 2006. And the 3D surface of parametric body model was flattened onto the 2D plane. 3 downscale ratios(0%, 10%, 15%) were applied to generated pattern to figure out what downscale ratio was suitable to make briefs with stretch fabric. 4 kinds of experimental briefs were made with stretch fabrics(0%, 10%, 15% downscale) and worn on the dressform. Subjective evaluation on the appearance was done and the data was analyzed by ANOVA with post-hoc test. Briefs pattern was generated through the process of flattening the parametric surface and arranging the patches to make briefs pattern by dart manipulation. The different ration of outline and area between 3D surface and 2D pattern were 0.22% and 0.09% respectively. It showed that a parametric model could provide a desirable pattern with minute size error. The results of subjective evaluation on the appearance of 4 experimental briefs showed that stretch briefs with 15% downscale ratio was evaluated most highly in most items. Findings imply that it is feasible to apply 3D parametric model to generate patterns for various items considering various fabric properties.

• Bulletin of the Korean Mathematical Society
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• v.61 no.4
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• pp.1033-1051
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• 2024

In this paper, we define a parametric variant of generalized Euler sums and construct contour integration to give some explicit evaluations of these parametric Euler sums. In particular, we establish several explicit formulas of (Hurwitz) zeta functions, linear and quadratic parametric Euler sums. Furthermore, we also give an explicit evaluation of alternating double zeta values ${\zeta}({\bar{2j}};\,2m+1)$ in terms of a combination of alternating Riemann zeta values by using the parametric Euler sums.

• The Journal of Korea Robotics Society
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• v.12 no.1
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• pp.19-25
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• 2017

A design methodology for parametric design optimization of washing machine door is presented. We develop a motion simulator and a robotic door to simulate the various motion of washing machine doors. The motion of the washing machine door is related to hinge parameters. Springs and dampers are usually used in the hinge of washing machine door for controlling motion of the door. A physical simulator of the door motion is used for finding candidate parameters of the hinge and a robotic door whose motion is controlled algorithmically is used for consumer tests. Through the consumer evaluation on the robotic motion, the optimized parameters are determined. We find the optimal parameters as a function of angle and angular velocity of the door.

• Korean Journal of Computational Design and Engineering
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• v.1 no.1
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• pp.45-55
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• 1996

This paper presents a new approach to non-parametric modeling of cutter swept surface (CSS) for cutting simulation. Instead of explicitly modeling cutter swept volumes, silhouette curves of the cutter surface are utilized in computing the z-value of the CSS at a grid point on the x,y-plane. The non-parametric evaluation of the CSS constitutes the integral part of 3-axis cutting simulation. The proposed method is more efficient than the existing ones in the case of conventional cutters (i.e., ball-end mills and flat-end mills), and more importantly, it enables the non-parametric modeling of the CSS for the round-end mills which was not possible with the existing methods.

• Journal of KIBIM
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• v.10 no.3
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• pp.22-32
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• 2020

Apartment building site planning is one of time consuming and labor-intensive tasks in architectural design field, due to its complexity in zoning regulations, building codes, local restrictions, and site-specific conditions. In other words, the process can be seen as a very complicated mathematical function with layers of variables and parameters, which ironically can be automated using computational methods on parametric tools. In this paper, a practical method of automating site planning of an apartment complex has been proposed by utilizing parametric approaches in Rhino 3D and Grasshopper. Two primary parameters, building heights and positions, determine the efficacy of building layouts under all regulatory standards, thus testing out numerous combinations of the two will produce some successful layout alternatives. For this, equation solver has been used for iterating the parametric model to sort out meaningful results among others. It also has been proven that the proposed process significantly reduced the time in site planning down to less than an hour on most cases, and many successful alternatives could be obtained by using multiple computers. Post evaluation processes such as day light and view shed analysis helped sort out the best performing ones out of functioning alternatives.

• Earthquakes and Structures
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• v.12 no.3
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• pp.375-388
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• 2017

Prior to modern seismic provisions, several bridges were not designed for seismic actions in moderate seismic areas. Precast multi-girder and slab bridges are typical highway overpass structures; they have a significant contribution to national bridge stocks. Since the seismic behavior is questionable, a preliminary parametric study is conducted to determine critical configurations and components. The results indicate that the behavior of the abutments, backfill soil, superstructure and foundation is normally satisfactory; however, the superstructure-abutment joints are critical for both single- and multi-span bridges, while the piers are also critical for longer multi-span configurations. The parametric results provide a solid basis both for detailed seismic assessment and development of design concepts of newly built structures in moderate seismic zones.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.57
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• pp.87-92
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• 2000

This paper describes a three dimensional parametric modeling system for transmission gears of tractor. In conventional design and manufacturing, information about three dimensional shapes has been described in engineering drawings. However drawing based design presents several problems; 1) communication errors between the designer and the modeller or manufacturer. 2) time taken and costs incurred in the design process. To solve these problems the system of parametric design based modeling has been proposed. Developed system in this paper consists of four steps; 1) parametric design of transmission gears with a solid modeler. 2) evaluation of gear geometry and strength. 3) dynamic simulation for gear interference check. 4) gear stress analysis with a CAE software. The proposed system has been tested in the fields and found to be a useful system.

• Journal of the Korean Geosynthetics Society
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• v.11 no.4
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• pp.71-77
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• 2012

In this study, data collected from geotechnical instrumentation, analyzers using Stochastic methods for evaluating the state of law and the automation program was developed. Is expected based data driven non-parametric methods modeling may be useful for evaluation of complex geotechnical instrumentation installed on the system from the measurements collected. Result of the verification of assessment techniques developed by the sensing data collected from the actual ground structures (reinforced retaining wall and tunnel), PCA analysis techniques applied to the present study was to determine the structural behavior and environmental factors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.4
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• pp.853-858
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• 2008

The structures of induction heating type pressure rice cooker are consisted of oven. top heater plate and locking ring. Because the pressure is applied to their structures, those should be necessary to do the safety evaluation. In this paper, structure analysis is performed for oven structures by using finite element method and as a results, optimal thickness is achieved. Especially, analysis fur anisotropic layered material is performed because oven is made of both stainless steel and aluminum. And both von Mises and Tsai-Wu failure criterion are applied for safety factor. Parametric method is used in order to get the optimal thickness for oven and top heater plate.